Speaker efficiency and power.
Agree!
My ACA drives a set off ESS AMT Pyramids (Custom built crossover) and a 7th order bandpass bass driver. 1/2 to 1 watt is way more than enough. Very rich detailed sound. I have two ACA amps. I used them both in the balanced configuration along with 24 volt supplies. We went back to using 1 amplifier - it was somewhat louder but not needed in the listening room we use. There may be some subtle difference in the balanced and unbalanced configuration indiscernible. The amp is silent and it sounds terrific!
Agree!
My ACA drives a set off ESS AMT Pyramids (Custom built crossover) and a 7th order bandpass bass driver. 1/2 to 1 watt is way more than enough. Very rich detailed sound. I have two ACA amps. I used them both in the balanced configuration along with 24 volt supplies. We went back to using 1 amplifier - it was somewhat louder but not needed in the listening room we use. There may be some subtle difference in the balanced and unbalanced configuration indiscernible. The amp is silent and it sounds terrific!
I like the switch on the front because mine would have to go on a rack, making the rear mounted switch awkward to try and get to. I have a tube phono pre like that and it’s a pita. I could see having the switch as close to the power inlet as possible though just to eliminate any noise.
Our research has shown that opinions are like one's own favourite body part, everyone has one. Luckily, we have everyone covered! The current breakdown of chassis actually pre-ordered now sits at:
Silver / Power Switch - 45%
Black / Power switch - 27%
Silver / No switch - 22%
Black / No switch - 7%
I'll post an update at the end of the week when we close the pre-orders.
Of course, this is DIY so go crazy. You can always add a hole later if the itch bites you. Here's the beginnings of an idea...
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Question allowable capacitor in C1 ?
I salvage these capacitors for free out of a Sony amplifier ( I tested them on my LCR meter DE-5000, they tested out like brand new can I use these will it negatively affect the frequency range or possibly damage any components being “10,000 UF nichicon CE 85C KG (K)”?, I figured 71 V rating makes no difference for the rating. The nichicon I charged up to 32 V three weeks ago and the voltage only drop to 29.4 V I figured that was a good sign even though they were old and used.
If that rating is too high I have free access to 48 new old stock ( SANGAMD TYPE 500 , 500-3352-02, 3600 MFD, 40 VDC) i’ve tested everyone of these on my LCR meter and only three of them tested low, I’ve charged each one of them on my DC power supply and they all hold voltage for several days without leaking down.
I’m saving my other Amp Camp Amp board that I had a problem with that was titled ( snap pop flash magic smoke ) to dissect and test every component and learn where I made my mistake I just don’t have time for that now .
I salvage these capacitors for free out of a Sony amplifier ( I tested them on my LCR meter DE-5000, they tested out like brand new can I use these will it negatively affect the frequency range or possibly damage any components being “10,000 UF nichicon CE 85C KG (K)”?, I figured 71 V rating makes no difference for the rating. The nichicon I charged up to 32 V three weeks ago and the voltage only drop to 29.4 V I figured that was a good sign even though they were old and used.
If that rating is too high I have free access to 48 new old stock ( SANGAMD TYPE 500 , 500-3352-02, 3600 MFD, 40 VDC) i’ve tested everyone of these on my LCR meter and only three of them tested low, I’ve charged each one of them on my DC power supply and they all hold voltage for several days without leaking down.
I’m saving my other Amp Camp Amp board that I had a problem with that was titled ( snap pop flash magic smoke ) to dissect and test every component and learn where I made my mistake I just don’t have time for that now .
Attachments
Hmm, lemme guess... There's an Arduino inside!
I'm planning to do the same, but on the preamp (B1) where the faceplate isn't hot: A touch sensitive switch, Arduino Pro-Mini and SSR to switch the PSU's of both the preamp and ACA. One switch for all to keep the missus happy.
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I have mine hooked up to Fusion-12 Tempests and it's ridiculous. Though I am using bass management with the L/R set to small crossed at 80hz to a pair of RSS315HF-4 sealed subs on a separate amp.
So far I have hooked the ACA's up to JBL S38(89db), JBL S312(92db), Nola clones(I think around 89-90db) and the Fusion-12 Tempests(98db)
It played all of the above speakers well loud enough. Perhaps not for some of the large spaces some people live in but for my humble sized room it is enough. Also, I don't mind shuttling my chair more near field, which I do from time-to-time anyway.
I did hook up the ACA to the Tempests full range as well and there was actually plenty of bass without the subs. As it stands now though, with the subs, there is no EQ applied to anything.
So far I have hooked the ACA's up to JBL S38(89db), JBL S312(92db), Nola clones(I think around 89-90db) and the Fusion-12 Tempests(98db)
It played all of the above speakers well loud enough. Perhaps not for some of the large spaces some people live in but for my humble sized room it is enough. Also, I don't mind shuttling my chair more near field, which I do from time-to-time anyway.
I did hook up the ACA to the Tempests full range as well and there was actually plenty of bass without the subs. As it stands now though, with the subs, there is no EQ applied to anything.
Hmm, lemme guess... There's an Arduino inside!
I'm planning to do the same, but on the preamp (B1) where the faceplate isn't hot: A touch sensitive switch, Arduino Pro-Mini and SSR to switch the PSU's of both the preamp and ACA. One switch for all to keep the missus happy.
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No Arduino inside yet (just a latching capacitive switch and a relay), but an Arduino controlled brain is coming, if it can handle the heat. Good idea to put it in the pre-amp. I'd like to incorporate a bunch of temperature and power data logging, add a DC trigger on/off, auto-power off, etc. I have a Pololu 2812 SSR, which appears to work great. Looking forward to mixing some coding and electronics
I have a Pololu 2812 SSR, which appears to work great. Looking forward to mixing some coding and electronics
I have the Sharp S108T02 SSR, but I see it has been discontinued. I'd imagine that there is a replacement.
I prefer to switch the mains for obvious reasons, but there will be a small wall wart running full time to provide 5V for the Arduino.
Looking forward to seeing what you come up with.
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I snagged a sliver one, no switch
Since I just built a silver one with no switch. Would have liked black but whatevs. Not sure I want to F up my perfectly good faceplate trying to retro a power switch. How about making a pile of extra front faceplates that are drilled with a core exchange for faceplates that aren't drilled?
The kit from March didn't come with an XLR plug, anyone know the part # of the one that comes with this kit? My anthem processor has XLR preouts so I may try running the pair balanced.
Once you wire the XLR plugs in can you still use an ACA as a stereo amp or do you need to swap wires around?
Great kit, can't wait to assemble another one!
Since I just built a silver one with no switch. Would have liked black but whatevs. Not sure I want to F up my perfectly good faceplate trying to retro a power switch. How about making a pile of extra front faceplates that are drilled with a core exchange for faceplates that aren't drilled?
The kit from March didn't come with an XLR plug, anyone know the part # of the one that comes with this kit? My anthem processor has XLR preouts so I may try running the pair balanced.
Once you wire the XLR plugs in can you still use an ACA as a stereo amp or do you need to swap wires around?
Great kit, can't wait to assemble another one!
Since I just built a silver one with no switch. Would have liked black but whatevs. Not sure I want to F up my perfectly good faceplate trying to retro a power switch. How about making a pile of extra front faceplates that are drilled with a core exchange for faceplates that aren't drilled?
The kit from March didn't come with an XLR plug, anyone know the part # of the one that comes with this kit? My anthem processor has XLR preouts so I may try running the pair balanced.
I've authored a page for you that details where you can get all the parts to bring your ACA aesthetic from V1.5 to V1.6. It also has the information on bringing a V1.0, V1.0B or V1.1 PCB up to current spec / able to use the new PSU.
ACA Upgrade Information – diyAudio Store
As for the black faceplate, you could order a new chassis and sell the old one in the swap meet or I could speak to Gianluca about adding yet another custom SKU to their system... remember the grass is always greener on the other side of the fence.
I finally got to hear a set of the monoblocks this last weekend at the Lone Star Audio Fest. They sounded quite nice and I was really impressed with them on a set of 89dB speakers. Since I’ve not heard any other NP amps do the ACA’s have a sonic character that is similar to one of the bigger amps? I ask because after reading through all the designs an Aleph J sounds intriguing to try after I get my ACA’s done as a first step up.
Hi All,
also a noobie here, new to ACA and close to new to electronics.
Pre-ordered the ACA V1.6 yesterday and as there is some time till delivery starts, I'm also looking for a matching (DIY)-Preamp. The preamp should be used with the ACA, the speakers are about 94dB and I use a CD-Player and Phono as a source. Balanced is not necessary, remote is fine but also not necessary.
I'm not quite sure if a passive Preamp will match the ACA (10kΩ Input Impedance is not that much and I don't know the sensitivity of the ACA). So maybe a Preamp with gain will be better.
Do you have any recommendations for me?
Erich
also a noobie here, new to ACA and close to new to electronics.
Pre-ordered the ACA V1.6 yesterday
and as there is some time till delivery starts, I'm also looking for a matching (DIY)-Preamp. The preamp should be used with the ACA, the speakers are about 94dB and I use a CD-Player and Phono as a source. Balanced is not necessary, remote is fine but also not necessary.I'm not quite sure if a passive Preamp will match the ACA (10kΩ Input Impedance is not that much and I don't know the sensitivity of the ACA). So maybe a Preamp with gain will be better.
Do you have any recommendations for me?
Erich
I was thinking internal. I know I'll use Left +, Right - or maybe the opposite since the + is wired to ground in this amp. I'll RTFM before I try to run it bridged though.
Nelson himself has said that you "can" run it bridged but you lose some of the sonic goodness. Has anyone compared the difference? I have to say I like the sound of the ACA better than I like the sound of the Anthem MCA-3 that I unplugged although I had to turn the volume WAY down when I plugged the Anthem back in.
Thank you! Exactly what I wanted. I had ordered the PSU already so that's covered.
I honestly wanted an anodized purple faceplate so I'll probably stick with the silver.
